un·​treat·​ed ˌən-ˈtrē-təd How to pronounce untreated (audio)
: not treated
untreated wastewater
especially : not improved or controlled medically
an untreated case of pneumonia
untreated diabetic patients

Example Sentences

Recent Examples on the Web Left untreated, precancerous cells may progress to cancer. Benjamin Ryan, NBC News, 17 Apr. 2023 Leptospirosis can cause liver and kidney damage, and may be fatal if left untreated. Primrose Freestone, CNN, 17 Apr. 2023 That also means that, if left untreated, the underground pimples can cause pretty bad scarring. Kristin Koch, Seventeen, 15 Apr. 2023 Hypothyroidism, a condition that left untreated, could cause coma and even death. Krista Stevens, Longreads, 4 Apr. 2023 If left untreated, there is a risk of developing neurological problems such as facial paralysis and nerve damage to the limbs. Jocelyn Solis-moreira, Popular Science, 27 Mar. 2023 Diabetes: If untreated, diabetes can cause irregular periods. Dr. Roshini Raj, Health, 14 Mar. 2023 Pain in the carpal tunnel region can make everyday activities like typing at your computer challenging if left untreated. Sarah Bradley, Verywell Health, 14 Mar. 2023 Sores can sometimes open and bleed if left untreated. Isadora Baum, Men's Health, 16 Feb. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'untreated.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

15th century, in the meaning defined above

Time Traveler
The first known use of untreated was in the 15th century

Dictionary Entries Near untreated

Cite this Entry

“Untreated.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/untreated. Accessed 5 Jun. 2023.

Medical Definition


un·​treat·​ed -ˈtrēt-əd How to pronounce untreated (audio)
: not subjected to treatment
an untreated disease

More from Merriam-Webster on untreated

Last Updated: - Updated example sentences
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